Control Techniques Unidrive SP, New Zealand

SP2402 reads as frame 2, 400 V class, second rating in that frame. Once you can read the four digits you can size a replacement off the label, and the three option slots tell you the rest of what you need.

Unidrive SP is the Control Techniques flagship and it is fully discontinued. It is also still running a large amount of New Zealand machinery, particularly timber, extrusion, winding and web handling.

Request a quote

Reading an SP model number

Four characters after the SP, and each one means something.

Position	Meaning
SP	Unidrive SP
First digit	Frame size. 1 is the smallest
Second digit	Voltage class
Last two digits	Rating within that frame and voltage

The voltage digit

Digit	Voltage class
2	200 to 240 V
4	380 to 480 V. Most New Zealand installations
5	500 to 575 V
6	500 to 690 V

Example	Reads as
SP1401	Frame 1, 400 V class, smallest rating
SP2402	Frame 2, 400 V class, second rating
SP3401	Frame 3, 400 V class
SP1202	Frame 1, 200 V class
SP5401	Frame 5, 400 V class

Frames 1 to 6 are wall or panel mounted. The larger frames are free standing or modular.

The frame size decides the footprint, the cable entry, the fan arrangement and the DC bus discharge time. So two drives of similar kW in different frames are not mechanically interchangeable, and a frame change means panel work.

The same drive does four different jobs

Worth understanding, because it explains why one model number turns up on very different machines.

Mode	What it does
Open loop	Ordinary induction motor speed control
Closed loop vector	Induction motor with encoder feedback. Full torque at zero speed
Servo	Permanent magnet servo motor
Regen	Front end returning energy to the supply

The mode is a parameter, not a different drive. The same SP2402 can be an open loop fan drive on one machine and a servo axis on another.

Two consequences. A replacement drive at defaults is in open loop, so a servo or closed loop axis will not behave until the mode is set. And closed loop and servo need a feedback module in a slot, which the drive does not come with.

Tell us what the drive is doing, not just its number.

The three option slots

The most important commercial content on this page. A bare SP is rarely the whole answer.

Slot	Menu
Slot 1	Menu 15
Slot 2	Menu 16
Slot 3	Menu 17

The slot maps to a menu number, which is how you tell which physical module a parameter or a trip belongs to.

Fieldbus modules

Module	Network
SM-PROFIBUS-DP	PROFIBUS DP
SM-DeviceNet	DeviceNet
SM-CANopen	CANopen
SM-Ethernet	Ethernet, Modbus TCP and EtherNet/IP depending on version
SM-EtherCAT	EtherCAT
SM-INTERBUS	INTERBUS

Modbus RTU over the drive's own serial port needs no module. So a drive on plain serial has empty slots, correctly.

Feedback modules

Module	Takes
SM-Universal Encoder Plus	The versatile one. Multiple encoder types
SM-Encoder Plus	Incremental encoder
SM-Resolver	Resolver feedback
SM-SLM	SLM feedback, used with certain motors

The drive has one feedback interface built in and the modules add more, or add types the built-in one does not handle.

Encoder and resolver are different measurement principles and the modules are not interchangeable. Look at what the motor actually has before ordering.

I/O modules

Module	Adds
SM-I/O Plus	Digital and analogue I/O
SM-I/O 32	High density digital I/O
SM-I/O Lite, SM-I/O Timer	Smaller I/O sets, timer functions
SM-I/O 120V, SM-I/O 24V Protected	I/O at other voltages, or with protection

SM-Applications, and where the machine program lives

The single biggest trap on this drive.

SM-Applications is a programmable motion coprocessor that sits in a slot and runs its own program. Winding and tension maths, cam profiles, line shafting, sequencing and coordination between drives all commonly live there.

Variant	Notes
SM-Applications	The standard coprocessor
SM-Applications Plus	More performance and memory
SM-Applications Lite	Reduced version, fewer interfaces

These are not interchangeable without checking, because a program written for one may need the resources of that variant.

Why it matters more than the drive

Situation	Outcome
Drive fails, module moved across	The program comes with it. Machine runs
Module fails, no source code on site	The machine's logic is gone
Replacement drive fitted, module left in the old one	Drive spins the motor, machine does nothing useful

So on any machine with an SM-Applications module, the module is the critical part and the drive is the commodity.

It is also the part most often skipped on a quote and thrown out with the old drive. Take the modules out before the drive leaves the site.

Keypads are options too

SM-Keypad and SM-Keypad Plus are ordered parts, and a drive can be supplied and run with a blank front. On a panel where the drive is commanded over fieldbus that is deliberate.

So a blank display is not necessarily a fault. But you need a keypad to commission a replacement, or a SMARTCARD and a PC tool. One keypad on the shelf serves a whole site.

The SMARTCARD is the difference between minutes and a day

Unidrive SP takes a SMARTCARD that clones a complete parameter set between drives. No laptop, no software, no licence.

Situation	Outcome
Card copy exists	Fit the drive, load the card, run
No copy	Every parameter re-entered, and the drive mode set correctly first
Several identical axes	One card commissions all of them

On a discontinued drive this is the cheapest insurance available. Take a card copy off every running SP now, label it, and keep it with the machine documentation.

The card carries the parameters. It does not carry the SM-Applications program, which is a separate backup taken with the programming tool.

Menu 11 identifies the drive

Useful when the label has gone, which on a dusty timber mill is common.

Menu 11 reports the drive model, the software version, the operating mode and what is fitted in each of the three slots.

So power it up and read menu 11 rather than guessing. It also tells you the drive's real history, which the invoice date does not.

And menu 10 holds the trip log, so an intermittently tripping drive has already recorded what happened.

Common trips

Trip	Meaning	Usually
OI.AC	Output over current	Mechanical load, or motor data and autotune
OV	DC bus over voltage	Braking resistor or ramp time
UV	DC bus under voltage	Supply dip or a lost phase
OI.br	Braking transistor over current	Resistor value or a shorted resistor
It.AC	Motor thermal overload	Load, or motor rated current set wrongly
Oht	Over temperature	Fan and airflow. Fans are replaceable
th	Motor thermistor	The motor or its thermistor wiring
Enc trips	Feedback fault	Encoder, cable or the feedback module
SL trips	Solutions Module in a named slot	The module, not the drive
EEF	Parameter memory failure	Defaults restored. Drive may be fine
HF trips	Hardware fault	The drive
Et	External trip	The machine told the drive to stop

Notice how many point outward. Encoder trips, thermistor, external trip and module trips are all outside the drive, and Oht is usually a fan.

EEF is the one that wastes the most money. The parameter memory has failed and the drive has reverted to defaults, so it powers up and runs and the machine behaves nothing like it should. People replace a drive that was working.

Send us the trip code with the model number. If the answer is a fan, a resistor or a module we will say so.

Braking is built in

On most SP frames the braking transistor is standard, so you add an external resistor rather than specifying a brake option.

That is the opposite of Danfoss, where the chopper is a factory-fitted option. So on an SP the question is whether the resistor is present and correctly rated, not whether the drive can brake.

An OI.br trip points at the resistor value or its wiring. An OV trip on deceleration points at the resistor being absent, undersized or disconnected. Tell us the resistor rating and we will check it.

Autotune, and why a swap can run badly

Autotune	Requires	Good enough for
Stationary	Load can stay coupled	Straightforward open loop
Rotating	Motor free to spin	Closed loop, servo, anything demanding

A replacement drive that holds poor torque at low speed, runs rough or trips under load has often only had a stationary autotune. On a closed loop axis that is not good enough.

It costs nothing to check and it is not a hardware fault.

Migrating to Unidrive M

Unidrive M is the successor and Nidec publishes mapping between the two. It is a real path and it is a project.

What changes
The option modules. SM modules do not fit an M drive
An SM-Applications program. Rewritten for the M platform
The parameter set. Mapped, not copied
The footprint and cable entry, usually
The keypad and the commissioning tool

So the honest comparison is a like-for-like SP against a migration. On a machine with years left in it, and particularly one with an SM-Applications program nobody has the source for, the SP is very often the cheaper and lower risk answer.

Supply of SP thins out over time and does not improve. If a machine matters, buy the spare while it exists.

Before ordering a replacement

Symptom	Check first
Drive runs, machine misbehaves	EEF in the trip log. Parameters may have defaulted
Machine will not sequence after a swap	The SM-Applications module
Trip naming a slot	The module in that slot
Oht trips	Fan and airflow
OV on deceleration	Braking resistor present and correctly rated
Poor torque at low speed	Drive mode, and whether the autotune was rotating
Servo axis will not run	Drive mode set to open loop at defaults, and the feedback module
Label gone	Read menu 11
Shelf spare will not run	DC bus capacitors after long storage

What to send us

The SP model number. It gives us frame, voltage and rating.

What is in each of the three slots. A photo with the covers off is quickest.

Whether there is an SM-Applications module, and whether anyone holds the program.

The operating mode. Open loop, closed loop vector, servo or regen.

The feedback device, if it is not open loop.

The trip code and the log from menu 10.

Whether you have a SMARTCARD copy.

The braking resistor rating.

What we can supply

Drives. Unidrive SP across frames and voltage classes, as new old stock, surplus and tested used.

Solutions Modules. Fieldbus, I/O, feedback and SM-Applications modules, supplied separately.

Accessories. SM-Keypad and SM-Keypad Plus, SMARTCARDs, cooling fans and braking resistors.

Whole axes. Where a machine needs drive, module, keypad and resistor together, we quote the set.

Used drives are powered up and tested before they ship. Where a unit has been in long storage we say so, because the DC bus capacitors need reforming before it goes on full mains.

A sensible SP spares holding

Item	Why
A SMARTCARD copy of every drive	Free to make, and it turns a failure into a swap
One keypad	Needed to commission anything, and serves the whole site
One drive per frame and rating on critical duty	Supply thins out and does not improve
A fan for each frame you run	The most common failure, and cheap
A spare SM-Applications module, where one is fitted	The part that holds the machine's logic

The card copies are the one to do this week. Everything else can wait; a parameter set that only exists inside a failing drive cannot.

We buy Unidrive SP

SP holds real value because the machines running it cannot buy new, and the Solutions Modules are worth money separately. An SM-Applications module is worth considerably more than the drive it came out of.

If you are stripping a machine, leave the modules in the slots, keep the keypad and keep any SMARTCARD with the drive. See Sell To Us.

Common questions

Can you get a part that is not listed on your site?
Usually. The site shows what we hold, not what we can source.

What does SP2402 mean?
Frame 2, 400 V class, second rating in that frame.

Can I move my modules into a replacement SP?
Yes. That is normally the cheapest route, and it brings any SM-Applications program with it.

Will my SM modules fit a Unidrive M?
No. Different option family. That is a large part of why a migration is a project.

The drive shows EEF.
Parameter memory failure. Defaults have been restored, which is why the machine is behaving strangely. The drive itself may be fine.

My servo axis will not run on the new drive.
A default drive is in open loop. The mode has to be set and the feedback module has to be present.

Do you supply used equipment?
Yes. On Unidrive SP it is usually the only option, and units are tested before they ship.

What is the lead time?
Ex stock items ship the next working day within New Zealand. We give you a firm lead time with the quote.

Do you quote in NZD?
Yes, in NZD including GST for New Zealand customers.

Send us your model numbers

The SP number sizes the drive. What is in the three slots decides whether it will actually run your machine. Quotes in NZD including GST.

Request a quote

Industech is an independent supplier of new, surplus and used industrial automation equipment. We are not an authorised distributor of, approved by, sanctioned by, or affiliated with Nidec Control Techniques or Emerson. Control Techniques, Unidrive, SMARTCARD and Solutions Module are trademarks of Nidec Control Techniques Ltd. PROFIBUS is a trademark of PROFIBUS Nutzerorganisation. EtherCAT is a trademark of Beckhoff Automation. EtherNet/IP is a trademark of ODVA. All trademarks, brand names and model numbers are the property of their respective owners and are used here for identification purposes only.